An apparatus and method for detecting an object approaching a vessel at rest on a water surface include a laser light curtain comprising at least one pulsed laser light beam extending radially from the ship toward a perimeter thereabout, the laser light curtain positioned spaced apart from and approximately...http://www.google.com.au/patents/US6737971?utm_source=gb-gplus-sharePatent US6737971 - Apparatus for detecting an object approaching a vessel and associated method
